The screening and diagnosisof cervical squamous intraepithelial lesions has both important clinical and public policy implications. In the United States, approximately 50 million women could be screened for cervical cancer each year; in addition, approximately 3 million women have further evaluation because of an abnormal result at time of screening. However, current cervical screening and diagnosis methods as well as methods for cervical cytological and pathological evaluation have been challenged for their effectiveness and economic consequences. The goal of this segment (Project 5) of the Program Project is to test hypotheses which evaluate the effectiveness and cost-effectiveness of (1) strategies for the diagnosis and screening of cervical precancer, including fluorescence spectroscopy, and (2) strategies for the interpretation of cervical cells and tissues, including quantitative cytology and quantitative pathology. Receiver operating characteristic(ROC) curve analysis will be performed to evaluate the effectiveness of diagnostic and screening technologies for cervical squamous intraepithelial lesions. Effectiveness will be evaluated by visual comparisons of the ROC curves and areas under the ROC curve for the various strategies. Decision-analytic models will be created, based on meta-analyses of data previously published in the literature as well as data collected from other portions of the Program Project. Cost-effectiveness analyses will be performed using the societal perspective, to determine the incremental cost-effectiveness ratios, measured in dollars per quality-adjusted life year, of various strategies to screen and diagnose cervical cancer and interpretcervical cells and tissues. The results from this Project will be used to enhance the development of cervical screening and diagnosis methodsin companion Projects. In addition, these results can provide policy and decision-makers regarding cervical cancer screening and diagnosis and cell and tissue interpretation with information regarding the effectiveness and cost-effectiveness of new technologies.